0. Programmer

I'm using an Arduino as ISP to flash the webserver to the AVR-NET-IO. See my previous post Dump ATMEGA32 on AVR-NET board using avrdude for how to convert the Arduino to a programmer and how to wire the connections between the Arduino (programmer) and the AVR-NET-IO. Do not connect AVR-NET-IO's own power source when it is connected to the Arduino (programmer).

1. ATmega32

The AVR-NET-IO uses the ATmega32 microcontroller about which the Arduino IDE does not know anything. Thankfully, Eric Conner has written a definition file for the ATmega32 needed by the Arduino IDE.

2. ENC28J60 network chip

The Pollin board also contains an ENC28J60 network chip. This cannot be addressed by the Arduino Ethernet library directly but there is a wonderful replacement library available from Norbert Truchsess at

palava.tv uses WebRTC and an open source central signaling server to enable peer to peer (P2P) video and audio chats and conferences. Soon the server might be available in an SD card image for the Raspberry Pi.

The version of a framework used in Java can be obtained by analysing its stack trace, especially the classname together with the line numbers. Maybe you should take care that your web server never prints that trace in case of errors.

Do not accept jobs that force you to make overtime hours that will be lost at the end of the month.

Baozi might be interesting to cook myself. Didn't have the time to go to the workshop.

A few introducery things about CAN and CANopen.

DMX, the protocol used for event technology (Veranstaltungstechnik) is very simple and can be used from Arduino, too. Maybe script a few cool effects using DMX isn't very hard. Just send a reset, a NULL, a node id and a value between 0 and 511 and your light starts to shine proportional - http://eh14.easterhegg.eu/pages/fahrplan/events/5772.html

A few very interesting details about how to sell your own electronics.

Most SD cards seem to have only half of the plastic housing filled with electronics. If you need a half-height SD card, e.g. such that it does not stick out of a notebook too much, you can simply cut the SD card in half. Before doing this, take a very bright LED (e.g. from your mobile) to shine through the plastic and see whether there is really no electronics in this half of the SD card. Then open the housing carefully. If it's really empty, you can cut it off.

This weekend I tried to repair a Hewlett Packard 8500A printer, 2 month after the 2 years guarantee was over. The display showed "Paper jam" error messages each time the printer was booted, which was a false error.

As it turned out, the problem was a broken cog, as can be found very often in your prefered search engine.